<?php
class Mwc_SystemPoint_Model_Mysql4_Expire_Collection extends Varien_Data_Collection_Db{
    protected $_expireTable;
 
    public function __construct(){
        $resources = Mage::getSingleton('core/resource');
        parent::__construct($resources->getConnection('systempoint_read'));
        $this->_expireTable= $resources->getTableName('systempoint/expire');
 
        $this->_select->from(
			array('expire' => $this->_expireTable),
			array('*')
		);

        $this->setItemObjectClass(Mage::getConfig()->getModelClassName('systempoint/expire'));
    }
}